EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION ORGANISATION EUROPEENNE ET MEDITERRANEENNE POUR LA PROTECTION DES PLANTES 17-23146 Pest Risk Analysis for Hygrophila polysperma 2017 EPPO 21 Boulevard Richard Lenoir 75011 Paris www.eppo.int [email protected] This pest risk analysis scheme has been specifically amended from the EPPO Decision-Support Scheme for an Express Pest Risk Analysis document PM 5/5(1) to incorporate the minimum requirements for risk assessment when considering invasive alien plant species under the EU Regulation 1143/2014. Amendments and use are specific to the LIFE Project (LIFE15 PRE FR 001) ‘Mitigating the threat of invasive alien plants to the EU through pest risk analysis to support the Regulation 1143/2014’. Cite this document as: EPPO (2017) Pest risk analysis for Hygrophila polysperma. EPPO, Paris. Available at: Photo: Hygrophila polysperma (Andreas Hussner) EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION Pest risk analysis for Hygrophila polysperma This PRA follows EPPO Standard PM5/5 Decision support scheme for an Express Pest Risk Analysis PRA area: EPPO region First draft prepared by: Andreas Hussner Location and date: Paris (FR), 2016-10-03/07 Composition of the Expert Working Group CHAMPION Paul (Mr) National Institute of Water and Atmospheric Research Ltd., Gate 10, Silverdale Road Hillcrest, 3216 Hamilton, New Zealand, [email protected] HUSSNER Andreas (Mr) Fa. Jackels Umweltdienste GmbH Siemensstr. 9 D-41366 Schwalmtal Germany, [email protected] LIEURANCE Deah (Ms) University of Florida, 3127 McCarty Hall B, PO Box 110500, FL 32611 Gainesville, Florida, United [email protected] NEWMAN Jonathan (Mr) Aquatic Plant Management Group, Centre for Ecology & Hydrology, Maclean Building, Benson Lane, Crowmarsh Gifford, OX10 8BB Wallingford, Oxfordshire, United Kingdom, [email protected] PETROESCHEVSKY Andrew N/A, PO Box 1708, NSW 2460 Grafton, Australia (Mr) Tel: +61-429455282 - [email protected] VAN VALKENBURG Johan National Plant Protection Organization, Geertjesweg 15, P.O. Box 9102, (Mr) 6700 HC Wageningen, Netherlands, [email protected] CHAPMAN Daniel (Mr) Centre for Ecology and Hydrology, Bush Estate, Penicuik, Edinburgh, UK [email protected] PESCOTT Oliver (Mr) Centre for Ecology and Hydrology, Wallingford, Maclen Building, Benson Lane, Crowmarsh Gifford, OX10 8BB, Wallingford, Oxfordshire, UK [email protected] TANNER Rob (Mr) OEPP/EPPO, 21 boulevard Richard Lenoir, 75011 Paris, France [email protected] 2 The pest risk analysis for Hygrophila polysperma has been performed under the LIFE funded project: LIFE15 PRE FR 001 Mitigating the threat of invasive alien plants to the EU through pest risk analysis to support the Regulation 1143/2014 In partnership with EUROPEAN AND MEDITERRANEAN PLANT PROTECTION ORGANIZATION And NERC CENTRE FOR ECOLOGY AND HYDROLOGY 3 Review Process • This PRA on Hygrophila polysperma was first drafted by Andreas Hussner • The PRA was evaluated under an expert working group at the EPPO headquarters between 2016-10-03/07 • Following the finalisation of the document by the expert working group the PRA was peer reviewed by the following: (1) The EPPO Panel on Invasive Alien Plants (October and November 2016) (2) The EPPO PRA Core members (December 2016) 4 Contents Summary 6 Stage 1: Initiation 9 Stage 2: Pest Risk Assessment 10 1. Taxonomy 10 2. Pest Overview 11 3. Is the pest a vector? 13 4. Is a vector needed for pest entry or spread? 13 5. Regulatory status of the pest 14 6. Distribution 15 7. Habitats and their distribution in the PRA area 17 8. Pathways for entry 18 9. Likelihood of establishment in the natural environment (PRA area) 19 10. Likelihood of establishment in the managed environment (PRA area) 19 11. Spread in the PRA area 20 12. Impact in the current area of distribution 20 12.01. Impacts on biodiversity and ecosystem patterns 20 12.02. Impacts on ecosystem services 22 12.03. Socio-economic impacts 23 13. Potential impact in the PRA area 23 14. Identification of the endangered area 24 15. Climate change 25 16. Overall assessment of risk 26 Stage 3: Pest risk management 28 17. Phytosanitary measures 28 18. Uncertainty 29 19. Remarks 29 20. References 30 Appendices Appendix 1 Projection of climate suitability for Hygrophila polysperma 34 Appendix 2 EU Biogeographical regions 42 Appendix 3 Images of Hygrophila polysperma 43 Appendix 4 Distribution maps of Hygrophila polysperma 48 5 Summary1 of the Express Pest Risk Analysis for Hygrophila polysperma PRA area: EPPO region (see https://www.eppo.int/ABOUT_EPPO/images/clickable_map.htm.) Describe the endangered area: Hygrophila polysperma is not naturalised in any natural environment within the EPPO region. The species is present in thermally heated waters (which are uncharacteristic of natural conditions) in Austria, Germany, Hungary and Poland. Hygrophila polysperma is a frost sensitive species. Climate modelling indicates that under the current projections, the majority of the EPPO region is unsuitable for the establishment of the species (see Appendix 1). Under current climatic conditions very small areas of Turkey, Greece and Algeria are marginally suitable along the Mediterranean coastline (the Mediterranean biogeographical region). Furthermore, thermally abnormal waters in other EPPO countries provide potential habitats for H. polysperma. Habitats within the endangered area include slow moving rivers, canals, irrigation and drainage systems, lakes, reservoirs. Main conclusions The results of this PRA show that Hygrophila polysperma poses a low risk to the endangered area under current climatic projections (very small areas of Turkey, Greece and Algeria are marginally suitable along the Mediterranean coastline) with a moderate uncertainty. Hygrophila polysperma is not naturalised in any natural environment within the EPPO region. The Expert Working Group does not recommend any phytosanitary measures for this species. The Expert Working Group recommends that the PRA is reviewed every ten years and/or when significant new information (e.g. naturalisation in natural environment of the endangered area or ecological data) becomes available. Entry and establishment Hygrophila polysperma is not naturalised in any natural environment within the EPPO region. The overall likelihood of Hygrophila polysperma entering the EPPO region is high. Hygrophila polysperma is imported into the EPPO region, traded and normally established in protected conditions, for example under glass. The species can establish in artificial, especially thermally influenced water bodies. Potential impacts in the PRA area Note: a lot of the information on impacts for this species, i.e. in the form of factsheets available on the internet, has been disqualified in this PRA because they contain generalised, unreferenced and unsupported statements about impacts throughout its invasive range. In thermally abnormal waters in the River Erft, Germany, H. polysperma has locally suppressed a native plant species (Personal Communication, A. Hussner, 2016, see Appendix 3, Fig. 5). In Poland, within a dense stand of H. polysperma, the oxygen concentration was found to be 3.1 mg per litre (Gabka & Owsianny, 2009), below concentrations required to support cyprinids (EEC, 1978). Negative effects on fishes and macroinvertebrates, which are reported from other countries where H. polysperma is invasive, can be expected if H. polysperma reaches similar levels of distribution. Hygrophila polysperma blocks the sunlight and reduces the wind induced mixing of the water column, and these effects are independent of the region in which H. polysperma becomes invasive. 1 The summary should be elaborated once the analysis is completed 6 Hygrophila polysperma reduces the functioning of drainage and irrigation systems and flood control canals. H. polysperma stands provide a suitable habitat for mosquitoes, which might carry diseases. Climate modelling indicates that under the current conditions, the majority of the EPPO region is unsuitable for the establishment of the species (see Appendix 1). Very small areas of Turkey, Greece and Algeria are marginally suitable along the Mediterranean coastline. Impacts are not predicted to happen under the current climate as the species will not establish. Habitats within the endangered area include slow moving rivers, canals, irrigation and drainage systems, lakes, reservoirs. Hygrophila polysperma is not naturalised in any natural environment within the EPPO region. Climate change Under climate change scenario RCP8.5 (Note: RCP8.5 is the most extreme of the RCP scenarios, and may therefore represent the worst-case scenario for reasonably anticipated climate change) for 2070s, Europe and the Mediterranean are projected to remain largely unsuitable for H. polysperma. However, some areas projected as marginally to moderately suitable appear in northern Portugal, southwest France, Greece, Italy, the eastern Adriatic coast, southern Turkey and Georgia. Under this climate change scenario, the biogeographic regions where the species can potentially establish are the Mediterranean, Continental, Black Sea and Atlantic biogeographical regions. Phytosanitary measures: The major pathway being considered is: Plants for planting Given the low risks for establishment and impact on the natural and managed environment within the endangered area the Expert Working Group does not recommend any phytosanitary measures for this species. National awareness raising measures: • There are no national prevention